Comparative study of biochar prepared from cow dung and sewage sludge and its application as an adsorbent for organic pollutants removal in water

• Published in: Environmental progress 2021-07, Vol.40 (4), p.n/a
• Main Authors: Suárez‐Vázquez, Santiago Iván, Cruz‐López, Arquímedes, Márquez‐Reyes, Julia Mariana, Flores Breceda, Héctor, García‐Gómez, Celestino
• Format: Article
• Language: English
• Subjects: Adsorbents; Adsorption; biochar; Cattle manure; Charcoal; Comparative studies; Contaminants; cow dung; Dung; Dynamic models; Fixed beds; fixed‐bed column; Methylene blue; Organic contaminants; Pollutant removal; Pollutants; Regeneration; Response surface methodology; Sewage sludge; Water pollution; Water treatment
• ISSN: 1944-7442; 1944-7450
• DOI: 10.1002/ep.13593

In this research, the synthesis of biochar from cow dung and sewage sludge and its application for the removal of organic contaminants using methylene blue (MB) as the model molecule was evaluated. Experiments were performed using different concentrations of adsorbent and MB and were optimized by a response surface methodology (RSM). Dynamic models were adjusted to the experimental data and the regeneration of the bed was studied. The results showed that the optimal conditions to favor the adsorption of MB, in a fixed bed and making a comparison between the two biochar sources, were those where an adsorbent biochar concentration of 5 g and initial MB concentration of 10 mg L−1 were used. The biochar prepared from cow dung presented the best adsorption conditions. Under these conditions, the breaking time was 172.73 min. The models of Thomas, Bohart–Adams, and Yoon–Nelson were applied for the study in fixed‐bed columns and it was observed that the models were adjusted satisfactorily. Regeneration was possible for three different cycles, slightly diminishing the performance of the bed with elution of HNO3. These results indicate that MB bed fixed adsorption on cow dung biochar is viable and suitable for water treatment.